自动分拣系统采用（）识别货物。
A.电子显示器
B.人工
C.无差错
D.条形码技术
参考答案：D
Whenever the government increases public services, ________because more workers are needed to carry out these services.
A．employment to rise
B．employment rises
C．which rising employment
D．the rise of employment
商业汇票的付款期限，最长不得超过（）个月。
A、1
B、2
C、3
D、6
